Win32API- GetForegroundWindows()

Ruby
1

Hi!

I’m playing with the API of Windows, but I haven’t found much
information about that (almost all is for VB -.- )

So I’d like to know where can I search for it.
Im trying to get de windows where the user is working, i have:

a = Win32API.new(‘user32’, ‘GetForegroundWindow’, [], ‘P’)
a.Call()

But it doesnt work… The GetForegroundWindow function doesnt need
params and it returns a handle of the windows, so i think it should
run…

Thanks.

P.S.: Sorry, English is not my first language :slight_smile:

2

Diego G. wrote:

Hi!

I’m playing with the API of Windows, but I haven’t found much
information about that (almost all is for VB -.- )

So I’d like to know where can I search for it.
Im trying to get de windows where the user is working, i have:

a = Win32API.new(‘user32’, ‘GetForegroundWindow’, [], ‘P’)
a.Call()

But it doesnt work… The GetForegroundWindow function doesnt need
params and it returns a handle of the windows, so i think it should
run…

Thanks.

P.S.: Sorry, English is not my first language :slight_smile:

Try changing your last parameter from ‘P’ to ‘N’:

a = Win32API.new(‘user32’, ‘GetForegroundWindow’, [], ‘N’)
window = a.Call()

David

3

Try changing your last parameter from ‘P’ to ‘N’:

a = Win32API.new(‘user32’, ‘GetForegroundWindow’, [], ‘N’)
window = a.Call()

David

Thanks, now it’s running :).

Just one more question. Now i got the handle of the window, any chance
to get the name of the window??

4

Diego G. wrote:

Try changing your last parameter from ‘P’ to ‘N’:

a = Win32API.new(‘user32’, ‘GetForegroundWindow’, [], ‘N’)
window = a.Call()

David

Thanks, now it’s running :).

Just one more question. Now i got the handle of the window, any chance
to get the name of the window??

You can use the GetWindowText API call. Pass it (1) your window handle,
(2) a string buffer into which the text is to be copied, and (3) the
maximum number of characters to copy to the buffer:

require ‘Win32API’

getForegroundWindow = Win32API.new(‘user32’, ‘GetForegroundWindow’, [],
‘L’)
getWindowText = Win32API.new(‘user32’, ‘GetWindowText’, [‘L’, ‘P’, ‘I’],
‘I’)

window_handle = getForegroundWindow.Call()
title_buffer = ’ ’ * 256
getWindowText.Call(window_handle, title_buffer, 256)
puts(title_buffer)

David

5

You can use the GetWindowText API call. Pass it (1) your window handle,
(2) a string buffer into which the text is to be copied, and (3) the
maximum number of characters to copy to the buffer:

require ‘Win32API’

getForegroundWindow = Win32API.new(‘user32’, ‘GetForegroundWindow’, [],
‘L’)
getWindowText = Win32API.new(‘user32’, ‘GetWindowText’, [‘L’, ‘P’, ‘I’],
‘I’)

window_handle = getForegroundWindow.Call()
title_buffer = ’ ’ * 256
getWindowText.Call(window_handle, title_buffer, 256)
puts(title_buffer)

David

Ok. Thank you very much !! Now It’s perfect.

Regards

6

Thanks a lot for the code
do you how is possible to get the text content of the browser when
displaying a flash app?

David M. wrote in post #763686:

Diego G. wrote:

Try changing your last parameter from ‘P’ to ‘N’:

7

recommend ffi, too, for windows api stuff:

win32api scares me.

8

On Mar 23, 8:32am, Roger P. [email protected] wrote:

recommend ffi, too, for windows api stuff:

Windows Examples · ffi/ffi Wiki · GitHub

win32api scares me.

Yeah, well, FFI scares me. It’s a PITA declaring structs, and it won’t
build with MSVC++.

Dan